How Many Calories Does Sex Burn? I Used My FItBit and My Boyfriend to Conduct An Unscientific Investigation

Aside from idly wondering how many calories sex burns or whether chewing food counts as a workout, I've never been that interested in exercise. I always considered reading an issue of Shape in the waiting room at the gynecologist’s office to be an acceptable form of aerobic activity, and I didn’t give much thought to wearable activity trackers like FitBit and Jawbone when they debuted a few years back. But this past year, after a prolonged bout of insomnia left me at my wit’s end, I bought a FitBit to monitor my sleep. I figured I would use it for a few weeks, bring print outs of my sleep cycles to my specialist, and then put it back in the box and try to return it to Target.

But then, like so many who had donned the fugly rubber bracelet before me, I became obsessed with FitBit. More specifically, I became obsessed with its ability to measure the calories burned doing mundane, every-day activities.

I didn’t become obsessed in a calorie-count-y or diet maven way , but in a scientific way. Having this little project going on in the background added a little pop of interest to the things I did every day. How many calories do I burn walking to the bus stop? Do I burn more or less if I walk there in heels? How many calories do I burn washing dishes? How many calories do I burn if, while washing said dishes, I jauntily sway side to side, like that dog from the Internet who salsa dances?

And so, of course, as my FitBit obsession began to exert an increasingly strong pull over me, I began to return to my earlier wonderings about sex — if household chores burned calories, surely doing it would too. There’s a lot of talk out there about whether, when, and how sex counts as an aerobic exercise, but the numbers vary so wildly (I read articles claiming everything from 30 to 100 as the number of calories burnt during a single sex session), and the info is always so general — every piece just noted how many calories are burnt “having sex.”

Considering the fact that “having sex” could mean anything from five minutes of eye-contact-free missionary position to getting a rim job while riding a dildo machine, I found these studies underwhelming. For, you see, despite the fact that I specifically selected a college so that I wouldn’t have to take a science class, the FitBit made me decide that I was now a health scientist, and the world was my cardio laboratory.

And as a newly-minted health scientist (in reality I have zero medical training and if you are looking for actual health advice you should go to an actual medical professional), I knew that science is all about details! That’s, like, the basis of the scientific method or something. And these articles had left out all of the important details! What kind of sex burned the most calories? What kind burned the least? Was there a way to game the system so that you could just give a really long and involved handjob instead of going to a cycling class? When does sex actually count as cardio?

These questions were relevant not just for my own obscene curiosity, but for the legions of productivity mavens out there who fill up our mighty Internet with guides to lifehacking your pizza and turning your smartphone into a hair dryer and whatnot. Wouldn't they want to know the best way to feel the burn while also feeling, you know, other stuff? I owed it not only to myself, but to them, to find the answers.


The Goal: To determine which sexual acts or positions burn the most calories.

The Method: To accomplish this, I will use a FitBit to count the number of calories burned while performing various sexual activities in five-minute increments.

The Hypothesis: It’s gotta be girl-on-top, right?

The Subject: I am a 32-year-old female, 5’2”, in medium-decent shape. I jog occasionally and am in generally good health (except for the insomnia thing). I am heterosexual, and was the penetrated partner in all of the experiments below (though if any of you want to check the cardio stats on some Bend Over Boyfriend action, I would be thrilled to peer-review your results).

In order to establish a baseline of how many calories my body consumed at rest, I monitored myself while doing a few non-sexual warm-up activities first:


Calories burned: 5


Calories burned: 11

With these parameters set, like the great Marie Curie, I began experimenting on myself.



Calories burned: 6


Calories burned: 5

Notes: Surprising, right? My hand-based masturbation wasn’t especially vigorous, but I was still surprised that, as an activity, it had the same cardio impact as watching Jensen Ackles (OK, fine, it was an activity brought on by watching Jensen Ackles).

Now that I had reached the limits of what I could discover on my own while in my room, pretending to be “working on my novel,” it was time to get a second test subject involved. So I asked my boyfriend if he would have extremely awkward sex with me that involved pulling out every five minutes and letting me look at an iPhone stopwatch while we did it. And, bless his heart, he said yes.

The Second Subject: My boyfriend is 28, also in generally good health, and is clearly a total fucking mensch for going along with all my crazy-ass plans. Living with me must be like living through a semi-nude episode of I Love Lucy every day. I’m sorry, honey.

And yes, we role-played the entire thing as Lizzy Caplan and Michael Sheen on Masters of Sex; quite frankly, I’m offended that you even felt like you had to ask.

And now, on to the hard numbers, as it were:



Calories burned:16


Calories burned: 8

Notes: Nothing too shocking here; giving a hand job feels like hard work, and apparently, it is. If you were able to give a hand job for a full hour, you’d burn nearly 200 calories...but something tells me that you’d probably never go on a second date.



Calories burnt: 9


Calories burnt: 8

Notes: This one was shocking, because performing oral sex can feel extremely effort intensive. But maybe it’s more effort intensive in a “trying to hold a yoga pose” kind of way. Also of note: both bouts of oral sex were performed with the receiver lying down; you can probably burn more calories standing up, but, frankly, I didn’t feel like it.



Calories burnt: 13


Calories burnt: 20

Notes: The more vigorous the intercourse was, the more calories were burned; but I felt like there was an inverse relationship here in terms of my actual sexual satisfaction. The slower intercourse felt better; the faster intercourse felt like, well, we were at the gym.


Calories burnt: 25

Notes: And I wasn’t even being that vigorous! The only real limit to the number of calories you can burn while on top is your imagination/ stamina/ confidence that you will not accidentally bounce up too hard then land kind of weird on the guy’s penis and he’s like “ahhhhh!” and then the whole thing is over.


Calories burnt: --

Notes: Despite deploying everything from the kitchen counter to a weird Ikea coffee table that one of my old roommates left, I just couldn’t make this one work for five minutes straight. Sorry. I’m a blogger, not a miracle worker, damn it!


Calories burnt: 24

Notes: This one was the biggest surprise for me, but it makes sense — doggystyle presents a great opportunity for both partners to support their combined weight, move freely, and get their pulses up.



While, as predicted, girl on top is the winner in terms of sheer cardio power, doggy style is a great way to become closer as a couple AND burn off the calories from that second slice of Domino’s Artisan at the same time.

Overall, a varied and semi-lengthy sexual encounter is a fun way to get your pulse rates up a bit, or maybe compensate for that half hour you spent looking for a parking spot instead of just parking like two blocks away from the movie theater. But, sadly, it is no real substitute for a trip to the gym (it is also no real substitute for a sexual encounter where you are just having fun and not thinking about something boring like burning calories).


My boyfriend was a good sport about the whole thing, but later that night, told me it’s basically either him or the FitBit. I’ll let you know which one I choose next week.